hot coat brush

i am going to use Polyester resin when i hot coatmy bonzer why kind of brush should i use: natural bristle, foam, nylon, polyester…

also has anyone ever put their resinbucket for laminating in a bucket of ice water to lengthen the gel time?

I always use natural bristle of the light coloured variety. I have used black also but if you loose any bristles they are obvious whereas light are not.

Not tried the ice bucket - here in the UK we spend most of our time heating everything up so it will go off !


Like Steve, I use light brown bristles. Make sure you slap the brush across something hard at least 30 times, to shake off weak bristles before hotcoating.

You want it to set off in about 15 minutes, just enough time to lay resin lengthwise, brush lengthwise, brush side across, then brush lengthwise again. Any longer, resin runs. Any less brushing, resin runs.

no for the lamination not the hotcoat.

Cool resin is thicker, harder to press into cloth at laps and rails.

Since #5, never needed more than about 10 minutes to lam any shortboard, up to 9’6" guns.

I used to watch RalphEhni, our glasser, lam 4 boards total in about 16 minutes.

I suspect, but don’t really know for sure, record can be Haut’s glasser of 35 years, as he prepped SEVEN boards and two batches of resin (one main bucket, another about a pint finish bucket), catalyst in, and finished around 20 minutes. Looked really good too, as the boards didn’t seem to show any pinbubbles.

Wow Lee! I’ve been trying to do multi-board batches; but only a few. Along with saving time, it seems that I am saving resin as well, because I can keep going until it runs out on the last board. If I need any on the last board, then I just mix a little more for a ‘catch up’ batch. Still, I think I would like to hire a glasser so I can shape more rather than be able to take on more glassing!

Rather than using a cooling bucket, just pour out the entire bucket onto the board as this cools the batch. A possible drawback of increasing the surface area of the resin is the evaporation of the vehicle. This is especially true when lamming with UV resin as more time is usually taken and the styrene is evaporated causing the resin to get thick at the end of the session.

i got more than enough time last night i mixed up a cool batch2/3 amount of cat. plus they cat and resin where in the fridge for about 30 minutes to cool em’ down. finished an entire board with the entire batch(less than 1/2 quart) with time to spare looks really good :slight_smile:


Use a good quality light bristle brush. It just makes it easier especially for newcomers. If you want to use the brush again and again. Rince twice in acertone and then rub bristles in washing powder and rince in hot water. I have used the same brush on about 12 boards and it is as still as good as new.

Sorry to sound like Roy or the penguin guy but the washing powder realy works even on my squeegees.

On the cooling thing No I wouldn’t do that. If your hoat coat takes too long it will not make a thick enough covering of the lam layer.

Keep Well

Don’t use foam! It will melt in the resin.

Go to Home Depot, or some other home improvement store and buy the budget brushes. They are made by ‘Chip’ and are the cheapest ones in the paint department. They are plain bristle with a non-painted natural wood handle. Go with the 4" one. If you were large enough to buy your goods from Revchem, you’d find the same stupid paint brush.

I would not put my resin in a bucket of ice water. Just work faster at wetting out your goods and go softer on the catalyst. Be careful not to go too fast. You will know when you go too fast by the cool cascading effect from the surface tension of your resin.

 Howzit Swifty, I keep my hot coat brush soaking in a tub of acetone when not in use just like my glossing brush. I have used the same brush for at least 300 boards and don't change to a new one til the bristles get to short from usage. A good brush is a good tool and you need to take good care of them. I am not a proponent of disposing of a brush after one use which some people do due to the high cost of acetone these days. Aloha,Kokua
Howzit Mr. Clean, Nice reply, I like a person who doesn't waste words,HA,HA. Aloha.Kokua

I have been having trouble with this old 6 stringer balsa computer.Just wanted to say that I agree with what you said about brushes.If you do it right you can make acetone go a long way.Same deal for Thalco squeeges.Keep em wet.

Howzit Mr. Clean, Yep nothing like a cracked and brittle Squeegee to ruin your day. I usually get about a year to a year and a half from 1 squeegee and keep the older one for smoothing our glass before a lamination. I don't throw anything thing out til it becomes useless. Aloha,Kokua

You Kokua//about smoothing da glass.I use one of those wide thin wallpaper smoothing brushes (not the ones used for glue).They are around 12 inches long and look like a big comb(in place of comb teeth it has bristles).Smooths the glass and stretches it a bit.One of the best tricks I ever learned.They cost around $5 at Home Depo.

…hey Kokua, i dunno…15 years ago when i tried the same i dont had good results…when i had going to use, the brush ´got gummy resin…i tried several times but without success…

Howzit reverb, Sounds like you weren't getting the brush into the acetone quick enough or not enough acetone to cover the whole brush except for the handle. As soon as my HC is brushed I put the brush in the dirtiest acetone first, wait 5 mins then into the next acetone bucket, then blow off the brush with air and put it in the clean acetone for a while. After that I have a separate container just for the brush that  always has clean acetone and that's where it stays til the next time I hot coat.I always drain the acetone out of the brush before putting it in the next bucket, No resin build up. I've actually saved gummy brushes by soaking them for a few days in acetone.Aloha,Kokua

An alternative to soaking in acetone is to rinse the brush in lacquer thinner after cleaning twice in acetone. The bristles will keep soft. If the resin has gelled on the brush, it’s pretty much gone.

i am one for reusing but i really don’t miss the days of standing over the acatone buckets…in the shop i use to work at we had the nast, dirty, semi clean, final rinse acatone system and it worked well at keeping the brushes going but now that i am a disposible bursh man i can’t imagine going back, kinda like the dustless sander… also, i think the acatone thing only really works if your using the brushs day in and day out… just like when i did drywall work, we never sharpned our knives because they stayed sharp from being scraped along walls all day long, now when i do an occasional dry wall job i have to sand the edge sharp before use…